The electrical connection of terminals on electrical equipment, such as circuit breakers used in particular in aeronautics, is usually accomplished using ring terminals having a hole in the center, these terminals being joined to contact lugs using devices such as locking screws having a threaded part screwing either directly into the lugs or into an inserted nut that is part of the contact lug or, for example, threaded shanks that are part of the lugs, on top of which a locking nut will be fastened.
In both cases, the terminals have the threaded part going through them and affixed to the contact lugs. These systems allow a good connection, but there is a risk that the screws or nuts will loosen due to vibrations or handling of cables proximate to the terminals.